Systems have been developed for packaging a medicament in a small vial and packaging a diluent in a separate, larger container. The vial and larger container can be subsequently connected together at the time of use, or earlier, for convenient safe mixing of the medicament and the diluent. By preparing such mixtures just prior to use, the problems attendant to the deterioration of mixtures having a short shelf life are avoided.
Such dual container systems are disclosed in the Abbott Laboratories, Inc. U.S. Pat. Nos. 4,614,267, 4,614,515, and 4,757,911. These systems typically include a diluent container in the form of an I. V. bag containing a standard diluent, such as a normal saline solution or dextrose. The diluent bag is provided for subsequent connection to a selected medicament container, such as a vial, containing the appropriate medicament in accordance with the individual prescription. In such a system, the additive medicament, which may be a solid (powder) or liquid, is added as a precise, predetermined, quantity into a precise quantity of diluent.
The diluent container has a port to which the medicament container (e.g., small vial) may be connected. Typically, the port in the diluent container includes internal threads, and the medicament container has one end with external threads for matingly engaging the diluent container port threads.
In order to maintain sterility of the medicament container and diluent container in the pre-assembled condition during shipping, storing, and handling, the medicament container is provided with a primary stopper and secondary closure or cover at its threaded end. Also, the diluent container is similarly provided with an internal plug inside the port and a secondary closure or cover over the port.
When the medicament container is to be threadingly engaged with the diluent container, the secondary closures are removed. However, the contents of the medicament container remain sealed within the container by the stopper, and the diluent container port remains occluded by the internal plug. As the medicament container and diluent container are screwed together, the outer end of the medicament container stopper is engaged by the outer end of the diluent container plug.
When it is desired to mix the medicament with the diluent, the flexible walls of the diluent container bag can be pushed in to allow the diluent container plug to be pulled further inwardly inside the bag and out of the port, and this necessarily pulls the engaged stopper out of the medicament container. The engaged plug and stopper then drop together inside the diluent container bag to the bottom of the bag.
Proper use of the dual container, reconstituted, drug system requires that the threaded engagement between the medicament container and the diluent container be properly established. In particular, the amount of threaded engagement must be sufficient to ensure the proper internal engagement between the medicament container stopper and the diluent container plug. Further, the threaded engagement between the medicament container and the diluent container must be sufficient to ensure a good, liquid-tight seal between the two containers.
With this type of dual container system, the proper threaded engagement is established by applying a predetermined, minimum torque. For example, in the above-identified Abbott Laboratories' system, the preferred minimum torque is about 10 inch-pounds. Typically, a user of the system, such as a pharmacist or nurse in a hospital, manually holds the diluent container (e.g., I. V. bag) in one hand while screwing the smaller, medicament container or vial into the port of the diluent container with the other hand.
Threading the two containers together with a final torque of about 10 inch-pounds requires some amount of effort. If a number of dual container systems must be assembled consecutively in a short period of time, one person may find the task to be somewhat tiring, and the muscles in the person's arms, hands, and fingers may become temporarily fatigued.
Thus, it would be desirable to provide a system that would permit a person to assemble such dual container systems without requiring such tiring procedures. The system should also preferably function in a manner that would minimize, if not eliminate, the possibility of trauma associated with repetitive motion when a person improperly attempts such procedures or performs such procedures for an inordinately long time.
Further, it would be advantageous if such an improved system could accommodate assembly of the containers with a predetermined torque and could function effectively to consistently provide the same, final torque to each dual container assembly.
It would also be beneficial if such an improved system could be operated relatively rapidly so as to accommodate assembly of the dual container units at a relatively high rate. This would accommodate high volume applications, such as in hospital pharmacies, wherein many such dual container units may be assembled each day.
It would also be desirable to provide an improved assembly system which would provide evidence of insufficient threaded engagement between the two containers and which would facilitate continued assembly of the two containers or reassembly as may be necessary.
Further, it would be advantageous to provide an assembly system that functions substantially automatically, with a minimum amount of human intervention, at a relatively low cost.
Finally, it would be desirable to provide an improved assembly system that operates in a manner which is consistent with, or which enhances, aseptic or sterile procedures.
The present invention provides a container assembly process and apparatus which can accommodate designs having the above-discussed benefits and features.